Mean:
E[Y] = E[3X₁ + X₂]
E[Y] = 3 E[X₁] + E[X₂]
E[Y] = 3µ + µ
E[Y] = 4µ
Variance:
Var[Y] = Var[3X₁ + X₂]
Var[Y] = 3² Var[X₁] + 2 Covar[X₁, X₂] + 1² Var[X₂]
(the covariance is 0 since X₁ and X₂ are independent)
Var[Y] = 9 Var[X₁] + Var[X₂]
Var[Y] = 9σ² + σ²
Var[Y] = 10σ²
If the function f is given by f(x)= 4x -3, find the value of f(2+h)
[tex]\\ \sf\longmapsto f(2+h)[/tex]
[tex]\\ \sf\longmapsto 4(2+h)-3[/tex]
[tex]\\ \sf\longmapsto 4h+8-3[/tex]
[tex]\\ \sf\longmapsto 4h+5[/tex]
There is a sequence of rigid transformations that takes A to A', B to B', and C to "
same sequence takes D to D'. Draw and label D':
Answer:
I think it's D
Step-by-step explanation:
Answer: I think its D
Step-by-step explanation:
Rigid transformation moves a shape without changing the size of the shape.
See attachment for the diagram that shows the position of D'
Someone please helppp
Answer:
k = 5/6
Step-by-step explanation:
First, we can make this have the form of a quadratic function, or ax²+bx+c=0. To do this, we can first subtract 10x from both sides to get
(2k+1)x²-8x=-6
Next, we can add 6 to both sides, resulting in
(2k+1)x²-8x+6 = 0
For a quadratic function of form ax²+bx+c=0, we can see that a=2k+1, b=-8, and c=6. We can then apply the quadratic equation, or
x= (-b ± √(b²-4ac))/(2a) to get our roots to be
x= (8 ± √(64-4(6)(2k+1)))/(2*(2k+1))
= (8 ± √(64-(48k+24)))/(4k+2)
= (8 ± √(40-48k))/(4k+2)
For the roots to be equal, we must have the two roots equal to each other. We can write this as
(8 + √(40-48k))/(4k+2) = (8 - √(40-48k))/(4k+2)
multiply both sides by (4k+2) to remove the denominator
8+√(40-48k) = 8 - √(40-48k)
subtract 8 from both sides to isolate the square roots
√(40-48k) = - √(40-48k)
The only number that is equal to its negative self (and is real) is 0. Therefore, √(40-48k) = - √(40-48k) = 0, so we have
√(40-48k) = 0
square both sides to remove the square root
40-48k = 0
add 48k to both sides to isolate the k and its coefficient
40 = 48k
divide both sides by 48 to isolate k
k = 40/48 = 5/6
What is the perimeter, rounded to the nearest tenth?
The area of the regular hexagon is 169.74 ft2.
A regular hexagon has an apothem with length 7 feet and an area of 169.74 feet squared.
What is the perimeter, rounded to the nearest tenth?
24.2 ft
28.3 ft
48.5 ft
56.8 ft
Answer:
48.5 ft
Step-by-step explanation:
Find the point on y axis which is equidistant from the point (5,-2) and (-3,2)
Answer:
(0, -2)
Step-by-step explanation:
a point on the y-axis. that means x=0.
so, the distance of (5, -2) to (0, y) is the same as the distance from (-3, 2) to (0, y).
the distance between (5, -2) and (0, y) is based on Pythagoras (the differences in x and y directions are the sides of a right-angled triangle, and the distance is its Hypotenuse, its baseline) :
distance² = (5-0)² + (-2 - y)² = 25 + 4 + 4y + y² = 29+4y+y²
but it is also
distance² = (-3-0)² + (2 - y)² = 9 + 4 - 4y + y² = 13 - 4y + y²
so, we get
29 + 4y + y² = 13 - 4y + y²
29 + 4y = 13 - 4y
16 = -8y
y = -16/8 = -2
their, the point on the y-axis being equidistant to both points is (0, -2)
Solve the following.
2x^2-7x-4/6x^2+7x+2<0
Can someone explain how to solve this.
Answer:
Which one have same variable gather or decrease up
Step-by-step explanation:
2x^2-4.6x^2=1.4x^2
-7x+7x=0
1.4x^2+2<0
x<0
For the function f(x)=x+9/7-4x find f^-1(x)
Answer:
Step-by-step explanation:
[tex]f(x)=\frac{x+9}{7-4x} \\put ~f(x)=y\\flip~x~and~y\\f(y)=x\\y=f^{-1}(x)\\y=\frac{x+9}{7-4x} \\flip~x~and~y\\x=\frac{y+9}{7-4y} \\x(7-4y)=y+9\\7x-4xy=y+9\\-4xy-y=9-7x\\or\\4xy+y=7x-9\\y(4x+1)=7x-9\\y=\frac{7x-9}{4x+1} \\or~f^{-1}(x)=\frac{7x-9}{4x+1}[/tex]
A trapezoid has two basses that measure 11 cm and 8 cm. The height of the figure is 5 cm. What is the area of the trapezoid? A) 95 cm2. B) 64 cm2. C) 47.5 cm2. D) 24 cm2
Answer:
C.47,5cm²
Step-by-step explanation:
The option which is not a solution of the equation 2x + 3y = 6 is:
(A) (0, 2)
(B) (1, 1)
(C) (-3, 4)
(D) (3, 0).
Answer:
Step-by-step explanation:
B OR TRUE
A car travels 25 m/s for 30 seconds. What distance did the car travel ?
Answer:
750 meters
Step-by-step explanation:
Answer:
750m
Step-by-step explanation:
Distance= Speed x Time
Speed = 25m/s
Time = 30s
Distance = 25 x 30
= 750 m
find 25th and 49th term of the sequence 50 ,46,42,38......
Answer: -46
Step-by-step explanation:
[tex]u_1=50=50-(1-1)*4\\u_2=46=50-(2-1)*4\\u_3=42=50-(3-1)*4\\...\\\\u_n=50-(n-1)*4\\\\\\u_{25}=50-(25-1)*4=-46\\\\\\Answer\ -46\\[/tex]
Find the volume of each figure. Round your answers to the nearest tenth, if necessary
Answer:
600
Step-by-step explanation:
Volume=l*b*h=5*12*10=600
A company determines that its weekly online sales, Upper S (t ), in hundreds of dollars, t weeks after online sales began can be estimated by the equation below. Find the average weekly sales for the first 3 weeks after online sales began. Upper S (t )equals2 e Superscript t
Answer:
$1272.36 ( average weekly sales for first 3 weeks )
Step-by-step explanation:
weekly online sales = S(t)
Determine average weekly sales for first 3 weeks
S(t) = 2e^t
total sales = ∫ S(t) dt
∴ Average weekly sales for first 3 weeks ( note : S(t) = 2e^t )
= [tex]\int\limits^3_0 {2e^t \, dt / ( 3 - 0 )[/tex]
= 2 [ e^t ] ³₀ / 3 = 2 ( e^3 - e^0 ) / 3 = 2 ( 6.3618 ) = 12.7236 hundreds
= $1272.36 ( average weekly sales for first 3 weeks )
Help anyone can help me do this question,I will mark brainlest.
Answer:
18. 28 cm*2
19. 24 m
Step-by-step explanation:
18. length × l = 16
l*2= 16
l = 4
RQ = 4 cm
PR =7cm
Area of parallelogram = b×h
= 7×4
=28cm*2
19. 8 +8 + (6-2) +( 6- 2)
=24 m
Is {3,…} a defined set
Answer:
no it's not a defined state it's undefined
Find the value of x
HELPP PLEASEE
GIVING 20 points!!!
Answer:
A 6.09
Step-by-step explanation:
Answer if you want tho...
Answer:
3 loaves 2 bananas left.
Step-by-step explanation:
The answer is asking how many loaves of three bananas Seth can make. 11 can be divided by 3 a total of 3 times, leaving a remainder of 2 bananas that would not be enough to make another loaf.
Two tangents drawn to a circle from a point outside it, are equal in length.prove it.
Can someone help me with this
Answer:
Step-by-step explanation:
The standard form for a circle is
[tex](x-h)^2+(y-k)^2=r^2[/tex] and what's important here is that the x- and the y- remain that way in the equation. Filling in our values,
[tex](x-(6))^2+(y-(-3))^2=25[/tex] which tells us that our center is
6 and -3 -------------------> (6, -3)
The radius is the square root of 25 which is 5.
Please help me with this problem.
Answer:
Step-by-step explanation:
Remark
The cos(60) = 1/2
The radii marked 6 is the adjacent side. You have to solve for the hypotenuse.
Why?
Because the hypotenuse is the distance from the center of the circle to the point of intersection of the angle. Once you have the hypotenuse, you can find the length of the tangent, which will lead to the area of the kite. Then take away 1/3 the area of the circle.
Hypotenuse
Cos(60) = 1/2
cos(60) = adjacent / hypotenuse Multiply both sides by the hypotenuse
hypotenuse * cos(60) = adjacent Divide by Cos(60)
hypotenuse = adjacent / cos(60)
adjacent = 6
hypotenuse = 6/0.5
hypotenuse = 12
Tangent
tangent^2 = 12^2 - 6^2
tangent^2 = 144 - 36
tangent^2 = 108
tangent = sqrt(108)
tangent = 6sqrt(3)
Triangles
The area of the triangle = 1/2 6sqrt(3) * 6
The area of the triangle = 18 sqrt(3)
There are two triangles so the area = 36 sqrt(3) That's the area of the kite.
Circle sector.
Area of the circle sector = 1/3 * pi * r^2
r = 6
Leave pi as it is.
Area of the circle sector = 1/3 * pi * 6^2
area of the circle sector = 12 pi
Answer
Area of the red part = area of the triangles - the area of circle sector
Area of the red part = 36*sqrt(3) - 12* pi
Which expression is equivalent to 15+3x
A) 3(5+x)
B) 5(3+x)
C) 3(5+3x)
D) 5(3+3x)
Answer:
3(5+x)
Step-by-step explanation:
15+3x
5*3 + 3*x
Factor out 3
3(5+x)
solve for x algebra help
Answer:
x=24
Step-by-step explanation:
Hi there!
We are given the following proportion:
[tex]\frac{2}{10}=\frac{3}{x-9}[/tex]
And we want to solve for x.
First, let's reduce [tex]\frac{2}{10}[/tex], as reducing fractions typically makes the process easier
[tex]\frac{2}{10}[/tex] is the same as [tex]\frac{1}{5}[/tex]
So:
[tex]\frac{1}{5}=\frac{3}{x-9}[/tex]
We can't do anything to [tex]\frac{3}{x-9}[/tex], but that's okay.
Now we can cross multiply, as this is a proportion
Multiply x-9 by 1 and 3 by 5
1(x-9)=3(5)
Multiply
x-9=15
Now this is an equation
Our goal is to isolate x on one side
So let's add 9 to both sides to remove it from the left side
x-9=15
+9 +9
_________
x=24
Hope this helps!
Answer:
24
Step-by-step explanation:
Cross multiply:
2(x - 9) = 2x - 18
3(10) = 30
2x-18 = 30
+18 +18
-----------------
2x = 48
----- -----
2 2
x = 24
Hope this helped.
Which decimal is equivalent to 48 over 100
a. 0.048
b. 0.48
c. 4.08
d. 4.8
Answer:
0.48
Step-by-step explanation:
hope it can work for you mark me as a brain liest
Find the length of x
. Assume the triangles are similar.
Answer:
x=2.24
Step-by-step explanation:
To do this problem, you must find the scale factor. Using two corresponding sides you can find it.
Using 2.4 and 3:
2.4 / 3 = 0.8
Scale factor: 0.8
Now find x:
2.8 × 0.8 = 2.24
x = 2.24
Hope this helped.
Which set of whole numbers but not natural numbers
Answer:
C
Step-by-step explanation:
C is the set with whole numbers as it contains 0 and natural numbers
jack o connel had $51,072 he wanted to share the money equally between 96 employees how much mone did each employee receive?
Answer:
$532
Step-by-step explanation:
We do 51,072 / 96 which is 532.
Each employee received $532.
The equation y=2(x-1)^2-5y=2(x−1)
2
−5y, equals, 2, left parenthesis, x, minus, 1, right parenthesis, squared, minus, 5 is graphed in the xyxyx, y-plane. Which of the following statements about the graph is true?
Answer:
(b) It is symmetrical about [tex]x = 1[/tex]
Step-by-step explanation:
Given
[tex]y = 2(x - 1)^2 - 5[/tex]
See attachment for options
Required
True statement about the graph
First, we check the line of symmetric
[tex]y = 2(x - 1)^2 - 5[/tex]
Expand
[tex]y = 2(x^2 - 2x + 1) - 5[/tex]
Open bracket
[tex]y = 2x^2 - 4x + 2 - 5[/tex]
[tex]y = 2x^2 - 4x -3[/tex]
A quadratic equation [tex]y = ax^2 + bx + c[/tex] has the following line of symmetry
[tex]x = -\frac{b}{2a}[/tex]
By comparison, the equation becomes:
[tex]x = -\frac{-4}{2*2}[/tex]
[tex]x = \frac{4}{4}[/tex]
[tex]x = 1[/tex]
Hence, the line of symmetry is at: [tex]x = 1[/tex]
(b) is true.
Answer: It is symmetrical about x=1
Step-by-step explanation:
A pair of shoes is on sale for 30% off. The original price is p. Which expression can be used to find the price of the shoes after the discount?
a) 0.30p
b) 0.70p
c) 1.30p
d) 30p
Answer:
Step-by-step explanation:
the answer is b
Find a (Round to the nearest tenth). PLS HURRY!!
Answer:
a = 56.3°
Step-by-step explanation:
tan(a) = 9/6 = 1.5
atan(1.5) = 56.31°
Answer:
[tex]\boxed {\boxed {\sf 56.3 \textdegree}}[/tex]
Step-by-step explanation:
We are asked to find the measure of angle a.
This triangle is a right triangle because of the small triangle in the corner representing a 90 degree or right angle. Therefore, we can use trigonometric functions. The three main functions are:
sinθ=opposite/hypotenuse cosθ= adjacent/hypotenuse tanθ= opposite/adjacentThe side measuring 6 is adjacent or next to angle a. The side measuring 9 is opposite angle a. Therefore, we will use the tangent function.
[tex]tan \theta= \frac{ opposite}{adjacent}[/tex]
[tex]tan \ a = \frac{ 9}{6}[/tex]
Since we are solving for an angle measure, we use the inverse trigonometric function.
[tex]tan ^{-1} * tan \ a = tan ^{-1} * \frac{9}6}[/tex]
[tex]a= tan ^{-1} * \frac{9}6}[/tex]
[tex]a= 56.30993247[/tex]
Round to the nearest tenth. The 0 in the hundredth place tells us to leave the 3 in the tenth place.
[tex]a \approx 56.3[/tex]
The measure of angle a is approximately 56.3 degrees.
The average of four different positive integers is 9. What is the greatest value for one of the integers?
Answer:
30Step-by-step explanation:
Sum of those 4 integers is:
4*9 = 36If the smallest ones are 1, 2 and 3, then the greatest possible integer is:
36 - (1 + 2 + 3) = 30